for promises that are broken
by quillquate
Summary: (but don't worry, they can be fixed with needle and thread) /In which Frisk wants to go to the Surface, Chara is bitter, and Asriel the just wants his best friend back a.k.a. the obligatory mermaid au.
" _Howdy!"_

" _Oh, did I scare you? Sorry, Mom tells me I can be a little too forward sometimes, haha."_

" _Say, what's your name?"_

" _You're not going to tell me? Why nooot?"_

" _...My name? You won't give me yours but you want to know mine?"_

" _I guess that's fair. Well. Howdy! My name's Asriel, Asriel Dreemurr."_

* * *

 _(Hey, Frisk, did you know? They say a sea witch lives in the trench. You know what trench I'm talking about, that one. The one that's so deep it doesn't seem to have an end.)_

You knock on the door. The house buried on the sides of the trench seems intimidatingly tall, with its royal purple bricks and large stature. It's kind of amazing that there's something like this thousands of miles under the sea. You knock again. There's still no answer, but you think you heard something (or someone) moving inside.

You raise your fist again and bang on the door. The sound echoes through the water and you watch the tiny bubbles trail after your hand. This time, you're definitely sure there's someone home, if the muttered cursing said anything about it.

 _(They say that this sea witch can grant you any wish, as long as you exchange something of equal value. Or maybe not. I guess it all depends on the sea witch themselves, haha.)_

One last time should do the trick, then. You give the door another solid rap. Something bangs on the wall repeatedly with frustrated groans coming from the other side. After a moment of silence, a scratchy voice says, "Yeah, yeah. I'm coming, cut it out before you break this rotting ." You smile to yourself in triumph as the door creaks open slowly. A pale face peeks out, eyeing you suspiciously. "What do you want."

"Can I come in?" you ask politely. "It's pretty cold out here."

" _May_ I come in," they say testily.

"May I come in?" you say. "It's pretty cold out here." The door opens a little wider. You take that as an invitation and step in.

 _(Maybe this is what you're looking for. Why don't you go visit?)_

Surprisingly, the inside is nice and homey, nothing like the dark cave you expected. A magical fire crackles next to a big armchair which looks absolutely heavenly after the long swim you had. Noticing you looking at the warm den with envy, the sea witch sighs and say resignedly, "Seeing as you're probably not going to leave me alone anytime soon, take a seat. I'll put on some tea."

"Thank you," you say. They nod curtly and swim towards where you presume is the kitchen. You sink into the cushy armchair which seems large enough to fit Triton himself. From your comfortable viewpoint, you can see that the living room is sparsely decorated. There's a bookshelf next to the fireplace. Curiously enough, it's completely bare except for the photo frame on the top shelf. Besides that is an ancient looking pot with reed-like plants with brown pods at the top.

Behind you is a rickety table that looks like it's about to fall apart. There are four chairs surrounding it.

Are they expecting someone?

You're interrupted from your thoughts when a high-pitched whistle reverberates throughout the house. There's some clanking coming from the kitchen before they come out again with two cups of tea. They shove one to you and sip aggressively from the other like their life depends on it.

The sea witch...looks nothing like you imagined, actually. When your friend Susie told you about a sea witch living in a dangerous, creepy place all by themselves, you thought of an old hag wearing dark overtones with cackles accentuating every sentence.

But they're nothing like that. They're made up of pastels and sharp angles; their fins are so ripped you're left wondering how they can even move around. Their tail isn't pitch black like the trench they live in, it's a warm amber. They don't have wrinkles and warts growing all over their face, they're not even old.

They're not much different than you, you realize. Nothing like the horrible sea witch you had expected to barter your soul with.

"So. Why are you here." They narrow their eyes at you after draining the cup dry (well, as dry as it can get. They're all underwater, after all).

"Hello, my name is Frisk," you say.

"I didn't ask for your goddamn name, I asked why you're here. Was it a dare? I bet it was. I bet that some idiot kid dared you to come to the scary sea witch's house and knock on their door. I bet you were idiotic enough to take that dare and come here. I bet you just came to bother me, me who just wants to be left alone. That's it, isn't it? Well?" Their face becomes progressively stormier as they spit out each sentence. Their already rosy cheeks are practically flaming at this point as they scrunch their eyebrows together to form an impressive scowl.

"So, what's _your_ name?" you ask, completely ignoring their (totally inaccurate) rant.

They move forward as if to yell some more but then something inside them seems to deflate like a balloon. "None of your fu- freaking business."

You wait patiently.

"Chara," they mutter.

"Nice to meet you, Chara, I'm Frisk."

And now they're back to glaring daggers at you. Chara bristles as they bite out, "Stop treating me like a kid! I'm older than you!"

"How old _are_ you?" you inquire, genuinely curious.

" _None of your business!"_ Chara yells. They look frazzled and look like they haven't gotten a wink of sleep since the beginning of time. They let out a long breath as you sit still, hands cupped around your rapidly cooling tea. They abruptly turn around and start taking deep breaths. You can hear Chara mumbling to themselves as their shoulders steadily start dropping from their tense position.

"Okay. Now, stop avoiding the question. Why are you here."

"I want to go to the Surface."

Chara laughs incredulously. "Go to the Surface. Ha, what a joke. Try again."

"I want to go to the Surface," you repeat.

"Are you kidding? It's illegal to go up there. Don't they teach you kids anything about law or whatever? If they catch you, you'll end up exiled! Just like m-" Chara stops immediately and looks like they regret being alive.

"Like you?" you finish curiously.

"No! I meant, um, just like the merfolk that did before!" They flail their arms rapidly while studiously avoiding all eye contact.

You crack a smile. "Well, I'm not very good at following rules."

Chara then looks at you, really looks at you. Looks at your ragged striped tank top and bandaged arms, looks at your scraped up tail, and most of all, looks at your determined eyes. Your determined eyes that won't take no for an answer.

"Why the hell not," they say, "not like it really affects me anyway." They look up from their bangs and flashes a wicked smile, full of teeth. "I never liked those prissy government officials anyway."

Chara's mouth tugs back into a frown when they catch sight of your blooming smile. "But don't think this means I like you or anything," they say hastily. "Merfolk are all the same. They're all horrible, nasty, all that bad stuff. But I'm willing to make a sacrifice in order to get back at them."

"Sure, Chara," you say patronizingly.

"Quit it!" they howl. "I'm _not_ a little kid!" You just laugh at them behind squinty eyes and instead sip your cold tea, enjoying the sight of them fuming like a little kid.

 _(I'm sure that you'll find your way from there easily.)_

 _(But remember, Frisk.)_

 _(Stay determined.)_

* * *

 **A/N:** after reading many of eristastic's fairy tale crossovers with undertale, i had to make one myself. it's based off "the little mermaid" but it doesn't stick to the plot like in the movie. so in other words... it's very loosely based on "the little mermaid." enjoy this little plot bunny until i flake off like i always do. (my fatal flaw as a writer is never being able to finish multi-chapter stories)


End file.
